So my 1mzfe Toyota engine requires 87 octane but the manual says that using 91 octane will result in "improved performance". What kind of "improved performance" is usually seen using a higher octane and will using a higher octane gas result in a cleaner and longer lasting engine in the long run?
Will higher octane result in a cleaner engine?
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increased drivability. Some engines see it ..some don't. The notion of "using anything above that which is required is wasteful" was spawned out of the government reaction to the fuel industry passively promoting premium as being "beneficial" to your engine. The notion was an exploitation of when there were very few injected engines in the USA (mainly higher end Euros-as though there were any other kind) that typically spec'd premium fuel. As injection became more common, all fuels were required to maintain minimum cleanliness standards ..but the fuel companies maintained the myth. Exxon paid millions in fines.
This established a counter myth of sorts. It implies that there is no difference in performance/drivability. This may or may not be the case depending on the engine in question. Even my mother's 86 Corsica 2.0 auto drove much better in hot weather (ac on etc.) with premium than it did with regular. It never appeared to equate to any fuel economy difference in this case
It's the same with my jeeps. Less knocking .."feels" better ..same miserable economy.
I'd say that, with the use of premium fuel, YPMV.
This established a counter myth of sorts. It implies that there is no difference in performance/drivability. This may or may not be the case depending on the engine in question. Even my mother's 86 Corsica 2.0 auto drove much better in hot weather (ac on etc.) with premium than it did with regular. It never appeared to equate to any fuel economy difference in this case
I'd say that, with the use of premium fuel, YPMV.
Yes and No. Yes partially because some higher octane gas contains more cleaner in the gas (proportionately speaking) than their 87 counterparts of the same brand.
No if your engine is out of tune to begin with, or you are running a certain brand that has same amount of detergent additive across the entire octane spectrum of the pump offering.
If you want your engine to burn clean, make sure it's well in-tune, and you give it a gentle warmup during acceleration and reduction of stop-n-go traffic.
Engine usually burns clean and stays clean if you do a lot of highway driving.
Q.
No if your engine is out of tune to begin with, or you are running a certain brand that has same amount of detergent additive across the entire octane spectrum of the pump offering.
If you want your engine to burn clean, make sure it's well in-tune, and you give it a gentle warmup during acceleration and reduction of stop-n-go traffic.
Engine usually burns clean and stays clean if you do a lot of highway driving.
Q.
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Oh ..I did want to add that in the past few years, fuel has surely deteriorated in quality. I've had to use fuel additives much more often. I didn't mean to imply that "top tier" fuels offer no cleanliness advantage over common fuel. I was approaching it from the drivability angle.
I've yet to see a head to head dyno or 1/4 mile show down between regular and premium ..or any method to show that you cannot get more drivability/performance out of using a premium fuel. Again, I've had engines that could care less ..and I've had those that received it quite well.
I've yet to see a head to head dyno or 1/4 mile show down between regular and premium ..or any method to show that you cannot get more drivability/performance out of using a premium fuel. Again, I've had engines that could care less ..and I've had those that received it quite well.
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Some engines may benefit from higher octane. My 5.3 will test and remap the fuel/spark curve if there is a change of about 5 gallons on the fuel guage, as in filling up the tank. I only benefit from higher octane on long highway runs. Around town, stop and go traffic, I see no improvment.
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Originally Posted By: tpitcher
...a good shot of Amsoil's PI sure would help keep 'er clean also, right??
I really never saw much of a need for this type of product until the past year or so. Now I feel that it's mandatory. I think Amsoil was in tune with the market on that one.
...a good shot of Amsoil's PI sure would help keep 'er clean also, right??
I really never saw much of a need for this type of product until the past year or so. Now I feel that it's mandatory. I think Amsoil was in tune with the market on that one.
If you're experiencing any knocking or pinging, step it up a grade. My roommate's Sport Trac calls for 87 but in the heat of summer, I'll sometimes get a knock on take-off. It goes away when I step him up to 89. Too-high octane in a car that doesn't require it can be harmful, as octane is little more than a combustion inhibitor. But it's not quite as harmful as knock. Go up just enough to quiet it down, if you're having that problem at all.
If cleanliness is a concern, run some Techron Fuel Injector Cleaner through it occasionally (My interval is every 10K miles.) It's worked wonders for several vehicles I've used it in.
If cleanliness is a concern, run some Techron Fuel Injector Cleaner through it occasionally (My interval is every 10K miles.) It's worked wonders for several vehicles I've used it in.
I've heard of accounts of carbon build up from runnig to high an octane.
Use the lowest you can get by with (quality fuel, of course).
Use the lowest you can get by with (quality fuel, of course).
Cars with knock sensors can take advantage of higher octane. I could see a significant improvement in my car that required at least 89 with 93 Chevron Supreme. I also use Lucas UCL at the moment and ocasionally run a bottle of Techron though it to make sure the system is as clean as possible.
Hook up a Scangauge and watch the timing setting for your comparison testing. Figure out a route and look for differences in the timing.
I run 98 octane in the Outback and 100 in the Mazda turbo. At least 20% better economy in the Mazda over std unleaded.
If the manual says that high octane will have increased performance, it means that the ignition timing map/program is made for premium, but will run on regular because of the knock sensor, and learned parameters after using regular for a while.
Go for the increased performance and gas mileage [there should be some]. Premium fuel also contains the most cleaners of any of the grades, although some dealers have the same amount in all grades.
Car Mfrs. would love to say regular only, so if they say premium is a helpful option, they are not kidding.
Go for the increased performance and gas mileage [there should be some]. Premium fuel also contains the most cleaners of any of the grades, although some dealers have the same amount in all grades.
Car Mfrs. would love to say regular only, so if they say premium is a helpful option, they are not kidding.
I run premium in both of my cars. My 86 Capri is carbureted and running premium allows me to run a slightly higher timing advance than with regular. It also seems to idle better and run smoother on it. My 88 mustang has a knock sensor and I see very noticeable gains with premium fuel. The EEC IV computer controls Ford was using by that point were smart enough to remap to the high octane fuel. I see about 4-6 miles to the gallon better on premium along with a bit more performance and smoother operation. My owner's manual states that I should use only 87 octane, but with my results I am getting, and with the engine having a knock sensor, the premium is worth it.
87 octane with Lucas UCL, MMO or any upper cylinder and fuel system lubercant and call it a day.
From Ford Motor Co....
http://media.ford.com/newsroom/feature_display.cfm?release=23040
///
Simply put, 10 to 15 percent of consumers may be unnecessarily pumping premium fuel into vehicles that don't need it. In fact, Ford's 2006 Model Year Fuel Recommendation Guide notes if your vehicle is experiencing starting, rough idle or hesitation problems, premium unleaded may cause the problems to become more pronounced.
...
You should also be sure that you are getting what you are paying for at the pump. Misangyi says the Environmental Protection Agency requires that all gasoline be certified with a minimum detergent level, but there are loopholes in the process.
Oil companies submit test results on a generic gasoline to the EPA for certification. But while the pump gas is supposed to perform at least as well as what was certified, there's no assurance that the fuel does.
Ford recommends BP fuel for all of its 2006 Ford-branded vehicles. BP is among the companies who routinely test their base gasoline, making sure that their gasoline has the same detergency performance as originally certified.
...
Since industry standards don't guarantee it, "Look for brands that promote good detergency," says Misangyi. "The ones who state it, are probably doing it right."
///
Drew
http://media.ford.com/newsroom/feature_display.cfm?release=23040
///
Simply put, 10 to 15 percent of consumers may be unnecessarily pumping premium fuel into vehicles that don't need it. In fact, Ford's 2006 Model Year Fuel Recommendation Guide notes if your vehicle is experiencing starting, rough idle or hesitation problems, premium unleaded may cause the problems to become more pronounced.
...
You should also be sure that you are getting what you are paying for at the pump. Misangyi says the Environmental Protection Agency requires that all gasoline be certified with a minimum detergent level, but there are loopholes in the process.
Oil companies submit test results on a generic gasoline to the EPA for certification. But while the pump gas is supposed to perform at least as well as what was certified, there's no assurance that the fuel does.
Ford recommends BP fuel for all of its 2006 Ford-branded vehicles. BP is among the companies who routinely test their base gasoline, making sure that their gasoline has the same detergency performance as originally certified.
...
Since industry standards don't guarantee it, "Look for brands that promote good detergency," says Misangyi. "The ones who state it, are probably doing it right."
///
Drew
Simply put, 10 to 15 percent of consumers may be unnecessarily pumping premium fuel into vehicles that don't need it.
So, does that mean that 85-90% are experiencing some improvement by using premium gas?
So, does that mean that 85-90% are experiencing some improvement by using premium gas?
Here's a funny one for ya. The sales staff at a Ford dealer in Dallas told me NOT to run premium unleaded in my brand new 97 Ranger 2.3 because....get this....it could eat a hole in the gas tank. Not because it wasn't recommended...not because it wouldn't help anything...but because they've had people come back with leaking gas tanks that they're blaming on premium fuel.
I did it anyway...really helped with the knock.
I did it anyway...really helped with the knock.
Originally Posted By: CBDFrontier06
Here's a funny one for ya. The sales staff at a Ford dealer in Dallas told me NOT to run premium unleaded in my brand new 97 Ranger 2.3 because....get this....it could eat a hole in the gas tank. Not because it wasn't recommended...not because it wouldn't help anything...but because they've had people come back with leaking gas tanks that they're blaming on premium fuel.
I did it anyway...really helped with the knock.
and I thought I had heard/seen it all.
Here's a funny one for ya. The sales staff at a Ford dealer in Dallas told me NOT to run premium unleaded in my brand new 97 Ranger 2.3 because....get this....it could eat a hole in the gas tank. Not because it wasn't recommended...not because it wouldn't help anything...but because they've had people come back with leaking gas tanks that they're blaming on premium fuel.
I did it anyway...really helped with the knock.
and I thought I had heard/seen it all.
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